The term refers to the time when the moon, which orbits Earth in a slightly elliptical trajectory, is at the absolute closest it can get while also being full. Other full moons have come close. But as a supermoon, Sunday’s was ever so slightly more magnificent.

‘‘The size difference between even the dimmest and brightest full moon is only a bit more than 10 percent,’’ said Shawn Domagal-Goldman, research space scientist at NASA’ Goddard Space Flight Center in Greenbelt, Maryland. ‘‘So the difference between other ‘supermoons’ and this one isn’t huge.’’

Known as the Sturgeon Moon (because of the abundance of sturgeon in the Great Lakes and Lake Champlain at this time of year), it became full officially at 2:09 p.m., just 26 minutes after coming closest to Earth.